It began as a harmless wager. Who could solve their case first? Professor and Mrs. Moriarty have a few weeks to kill before their theater opens. Happily, two small cases drop in their respective laps. Moriarty has what looks like a scheme to swindle Army veterans out of their discharge pay. Angelina must find a missing servant by winkling her way into a circle of officers' wives. Neither case seems terribly challenging; just enough to provide an agreeable competition. But as soon as they start asking questions, things take an ugly turn. Moriarty discovers an army barracks riddled with corruption. Angelina uncovers a terrible secret at the heart of the circle of officers and wives. When Sherlock Holmes returns from a mission in India, he confirms her worst fears. Then a man is murdered, and a good friend is blamed. Scotland Yard sends Holmes to catch their suspect. The Moriartys must use all their courage and ingenuity to rescue their friend, stop a series of loathsome crimes, and put a cold killer behind bars.